Stephen Sheppard Shlomo Angel Daniel Civco
Williams College
The PIs will investigate the causes and the consequences of land and urban use expansion in a global sample of 120 cities stratified by size, geographic region, and level of economic development. These data cover two time periods that correspond to the two most recent censuses. This investigation is of central scientific and policy importance, especially for cities in developing countries, where the urbanized population is expected to double, from 2 billion to 4 billion in the next 30-35 years. With increasing incomes in the developing countries, the consumption of land by their cities will likely double in the next 25 to 30 years. The PIs will assess the consequences of different levels of urban land consumption for human welfare in general, and for urban poverty in particular. The PIs collect local data using local surveyors, improve and assess the land cover classification for the sample, measure social and economic impacts of urban expansion and model the effects of local policies on urban expansion.
Broader Impact. The analyses the PIs will conduct is the first to use a global sample to explore the relative importance of factors such as population growth, income, transportation costs and infrastructure, economic structure of the urban area and local regulatory policies on urban expansion. The analysis is also the first to evaluate, in a global context, the impacts of urban expansion on housing affordability, access to sanitary and transportation infrastructure, and conditions in the most impoverished areas of cities. The broader impact of the research rests on the foundation for global cities to understand and predict the magnitude of urban expansion that can be expected. Such understanding allows cities to manage urban expansion and design humane and sustainable public policies.